<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<script type="text/javascript">
    function show(){
        alert(this);
    }
    

    show(); //简写
    show.call();//完整的写法
    show.call(12);// call可以改变this的对像

 

    function show2(a,b){
        alert('this是'+this+'\na是:'+a+'\nb是'+b);
    }
    
    show2(12,4);
    show2.call('abc',12,4);
</script>
</head>
<body>
	
</body>
</html>